van Ekeren Wessel W A, Pereira Alexandre M, Albuquerque Marcelo, Costa Luciano T, Younesi Reza
Department of Chemistry-Ångström Laboratory, Uppsala University, SE-751 21 Uppsala, Sweden.
MolMod-CS, Physical Chemistry Department, Institute of Chemistry, Fluminense Federal University, Campus Valonguinho, CEP 24020-141 Niterói, Rio de Janeiro, Brazil.
ACS Appl Mater Interfaces. 2024 Oct 2;16(41):56355-65. doi: 10.1021/acsami.4c11797.
This study investigates a group of electrolytes containing NaPF or NaBF salts in phosphate- and ether-based solvents for high-mass loading sodium-ion batteries. It explores physicochemical properties such as ionic conductivity, dynamic viscosities, and nonflammability. The combination of experimental with computational studies reveals detailed insights into the physicochemical properties of the nonflammable liquid electrolytes. Diglyme-based electrolytes become nonflammable with 50 vol % phosphate solvents, while tetraglyme-based electrolytes require 70 vol %. The solvation structure has been investigated using NMR and is combined with computational studies to provide information about properties such as solvation structure, ionic conductivity, and viscosity. The molecular dynamic simulations confirm the enhanced solvation in diglyme-based liquid electrolytes observed experimentally by Na-NMR. Despite lacking sufficient electrochemical stability, this work provides a fundamental understanding of the solvation structure and physicochemical properties of a novel electrolyte system. This is an important contribution to be applied in future electrolyte design rationale.
本研究调查了一组用于高质量负载钠离子电池的、包含NaPF或NaBF盐且以磷酸盐和醚为溶剂的电解质。它探索了诸如离子电导率、动态粘度和不可燃性等物理化学性质。实验研究与计算研究相结合，揭示了对不可燃液体电解质物理化学性质的详细见解。基于二甘醇二甲醚的电解质在含有50体积%的磷酸盐溶剂时变得不可燃，而基于四甘醇二甲醚的电解质则需要70体积%。已使用核磁共振研究了溶剂化结构，并将其与计算研究相结合，以提供有关溶剂化结构、离子电导率和粘度等性质的信息。分子动力学模拟证实了通过钠核磁共振实验观察到的基于二甘醇二甲醚的液体电解质中增强的溶剂化作用。尽管缺乏足够的电化学稳定性，但这项工作为新型电解质体系的溶剂化结构和物理化学性质提供了基本的理解。这是对未来电解质设计原理应用的一项重要贡献。
